import { EventEmitter } from "eventemitter3";
import type {
  Provider,
  ProviderEventMap,
  RequestArguments,
} from "./types/provider.js";
import type { Signer } from "./types/signer.js";
import { YiSigner } from "./yiSigner.js";

export class ProviderEventEmitter extends EventEmitter<
  keyof ProviderEventMap
> {}

export class YiProvider extends ProviderEventEmitter implements Provider {
  private readonly projectId: string;
  private signer: Signer | null;

  constructor(projectId: string) {
    super();
    this.projectId = projectId;
    this.signer = null;
  }

  public async request<T>(args: RequestArguments): Promise<T> {
    try {
      if (!this.signer) {
        switch (args.method) {
          case "eth_requestAccounts": {
            const signer = this.initSigner();
            await signer.handshake(args, this.projectId);
            this.signer = signer;
            break;
          }
          default: {
            throw new Error(
              "Must call 'eth_requestAccounts' before other methods",
            );
          }
        }
      }
      return this.signer.request(args) as Promise<T>;
    } catch (err) {
      return Promise.reject(err);
    }
  }

  async disconnect() {
    this.signer?.cleanup();
    this.signer = null;
    this.emit("disconnect");
  }

  private initSigner() {
    return new YiSigner({
      callback: this.emit.bind(this),
      projectId: this.projectId,
    });
  }
}